// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2008-2015 Gael Guennebaud <gael.guennebaud@inria.fr>
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.

#ifndef EIGEN_SPARSE_CWISE_UNARY_OP_H
#define EIGEN_SPARSE_CWISE_UNARY_OP_H

namespace Eigen {

namespace internal {

    template <typename UnaryOp, typename ArgType>
    struct unary_evaluator<CwiseUnaryOp<UnaryOp, ArgType>, IteratorBased> : public evaluator_base<CwiseUnaryOp<UnaryOp, ArgType>>
    {
    public:
        typedef CwiseUnaryOp<UnaryOp, ArgType> XprType;

        class InnerIterator;

        enum
        {
            CoeffReadCost = int(evaluator<ArgType>::CoeffReadCost) + int(functor_traits<UnaryOp>::Cost),
            Flags = XprType::Flags
        };

        explicit unary_evaluator(const XprType& op) : m_functor(op.functor()), m_argImpl(op.nestedExpression())
        {
            EIGEN_INTERNAL_CHECK_COST_VALUE(functor_traits<UnaryOp>::Cost);
            EIGEN_INTERNAL_CHECK_COST_VALUE(CoeffReadCost);
        }

        inline Index nonZerosEstimate() const { return m_argImpl.nonZerosEstimate(); }

    protected:
        typedef typename evaluator<ArgType>::InnerIterator EvalIterator;

        const UnaryOp m_functor;
        evaluator<ArgType> m_argImpl;
    };

    template <typename UnaryOp, typename ArgType>
    class unary_evaluator<CwiseUnaryOp<UnaryOp, ArgType>, IteratorBased>::InnerIterator
        : public unary_evaluator<CwiseUnaryOp<UnaryOp, ArgType>, IteratorBased>::EvalIterator
    {
    protected:
        typedef typename XprType::Scalar Scalar;
        typedef typename unary_evaluator<CwiseUnaryOp<UnaryOp, ArgType>, IteratorBased>::EvalIterator Base;

    public:
        EIGEN_STRONG_INLINE InnerIterator(const unary_evaluator& unaryOp, Index outer) : Base(unaryOp.m_argImpl, outer), m_functor(unaryOp.m_functor) {}

        EIGEN_STRONG_INLINE InnerIterator& operator++()
        {
            Base::operator++();
            return *this;
        }

        EIGEN_STRONG_INLINE Scalar value() const { return m_functor(Base::value()); }

    protected:
        const UnaryOp m_functor;

    private:
        Scalar& valueRef();
    };

    template <typename ViewOp, typename ArgType>
    struct unary_evaluator<CwiseUnaryView<ViewOp, ArgType>, IteratorBased> : public evaluator_base<CwiseUnaryView<ViewOp, ArgType>>
    {
    public:
        typedef CwiseUnaryView<ViewOp, ArgType> XprType;

        class InnerIterator;

        enum
        {
            CoeffReadCost = int(evaluator<ArgType>::CoeffReadCost) + int(functor_traits<ViewOp>::Cost),
            Flags = XprType::Flags
        };

        explicit unary_evaluator(const XprType& op) : m_functor(op.functor()), m_argImpl(op.nestedExpression())
        {
            EIGEN_INTERNAL_CHECK_COST_VALUE(functor_traits<ViewOp>::Cost);
            EIGEN_INTERNAL_CHECK_COST_VALUE(CoeffReadCost);
        }

    protected:
        typedef typename evaluator<ArgType>::InnerIterator EvalIterator;

        const ViewOp m_functor;
        evaluator<ArgType> m_argImpl;
    };

    template <typename ViewOp, typename ArgType>
    class unary_evaluator<CwiseUnaryView<ViewOp, ArgType>, IteratorBased>::InnerIterator
        : public unary_evaluator<CwiseUnaryView<ViewOp, ArgType>, IteratorBased>::EvalIterator
    {
    protected:
        typedef typename XprType::Scalar Scalar;
        typedef typename unary_evaluator<CwiseUnaryView<ViewOp, ArgType>, IteratorBased>::EvalIterator Base;

    public:
        EIGEN_STRONG_INLINE InnerIterator(const unary_evaluator& unaryOp, Index outer) : Base(unaryOp.m_argImpl, outer), m_functor(unaryOp.m_functor) {}

        EIGEN_STRONG_INLINE InnerIterator& operator++()
        {
            Base::operator++();
            return *this;
        }

        EIGEN_STRONG_INLINE Scalar value() const { return m_functor(Base::value()); }
        EIGEN_STRONG_INLINE Scalar& valueRef() { return m_functor(Base::valueRef()); }

    protected:
        const ViewOp m_functor;
    };

}  // end namespace internal

template <typename Derived> EIGEN_STRONG_INLINE Derived& SparseMatrixBase<Derived>::operator*=(const Scalar& other)
{
    typedef typename internal::evaluator<Derived>::InnerIterator EvalIterator;
    internal::evaluator<Derived> thisEval(derived());
    for (Index j = 0; j < outerSize(); ++j)
        for (EvalIterator i(thisEval, j); i; ++i) i.valueRef() *= other;
    return derived();
}

template <typename Derived> EIGEN_STRONG_INLINE Derived& SparseMatrixBase<Derived>::operator/=(const Scalar& other)
{
    typedef typename internal::evaluator<Derived>::InnerIterator EvalIterator;
    internal::evaluator<Derived> thisEval(derived());
    for (Index j = 0; j < outerSize(); ++j)
        for (EvalIterator i(thisEval, j); i; ++i) i.valueRef() /= other;
    return derived();
}

}  // end namespace Eigen

#endif  // EIGEN_SPARSE_CWISE_UNARY_OP_H
